SALT LAKE CITY, Ut-An adult male living on a reservation in Utah has become ill with the plague after taking care of a relative's sick cat in Arizona.
Officials are not saying whether fleas on the cat are the cause of the man's illness, but the plague has been reported in northern Arizona in the last month.
The human form of the plague is rare and believe to be caused by fleas that feed on rodents infected with the bacteria, Yersinia pestis. The plague can develop three different ways in humans. The infection can enter the lymph nodes, the bloodstream, or the lungs. When the infection is in the lymph nodes it is called bubonic plague, which killed millions of Europeans during the Middle Ages.
Present day, however, there has not been an outbreak of the plague in an urban area since 1924, when people became infected in Los Angeles. There are naturally occurring areas in places through the US where rodents live. There are an estimated 10-15 rural cases reported each year. The "hot zones" within the US run from the Pacific Coast to the Great Plains, and from southwestern Canada to Mexico.
American outbreaks usually occur in northern Arizona, southern Colorado, California, southern Oregon, and Nevada.
Globally, the World Health Organization (WHO) estimates 1,000-3,000 cases of the plague annually.